Miko Watanabe is the late wife of Sensei Kanoi Watanabe and late mother of Cameron "Cam" Watanabe. She was trained in the art of the Samurai and was also in possession of the samurai amulet. After Kiya was departed and was expelled from the Wind Ninja academy for his theft, Miko married Kanoi and gave birth to their only child. At some point early in Cameron's life, Miko fell ill. Before she died from her illness, Miko forbade Kanoi from training Cam in the ways of the ninja, because of the dangerous lifestyle required for Ninjas. When Cam went back in time to retrieve the amulet, he met his mother as a young woman. She had studied the ways of the samurai under her father (which would make him Cam's maternal grandfather), and she became the first female student to enroll at the Academy after she defeated Kanoi in a sword fight.

Since she did not know who Cam was, when Cam told her of his mother's choice of not letting him become a ninja, she replied that his mother would've changed her mind if she could see how dedicated Cam was. When her brother-in-law sought the amulet, he wore clothes similar to Cam's so that Miko believed that Cam was the thief. Before judgment could be passed on Cam, Kanoi revealed Kiya to be the thief, resulting in a sword fight between Kiya and Cam when Miko's amulet chose Cam. The end result was Kiya's expulsion and his becoming of Lothor. Miko told Cam to keep the amulet as he was pulled back into the time warp to the present. It allowed Cam to become the Green Samurai Ranger.